基于应变楔模型的砂土地基水平循环受荷桩简化分析方法  

Simplified analysis method for cyclic ally laterally loaded pile in sand based on strain wedeg model

作　　者：邢康宇 吴文兵[1,2] 张凯顺 刘浩 XING Kangyu;WU Wenbing;ZHANG Kaishun;LIU Hao(Faculty of Engineering,China University of Geosciences,Wuhan 430074,Hubei,China;Engineering Research Center of Rock-Soil Drilling&Excavation and Protection,Ministry of Education,Wuhan 43017,Hubei,China;China Railway Engineering Consulting Group Zhengzhou Deign Institute,Zhengzhou 450001,Henan,China)

机构地区：[1]中国地质大学工程学院,湖北武汉430074 [2]岩土钻掘与防护教育部工程研究中心,湖北武汉430074 [3]中铁工程咨询集团有限公司郑州设计院,河南郑州450001

出　　处：《河南理工大学学报（自然科学版）》2021年第5期153-159,共7页Journal of Henan Polytechnic University（Natural Science）

基　　金：国家自然科学基金资助项目(51678547,51878634);中国科协青年人才托举工程项目(2018QNRC001)。

摘　　要：为反映水平循环荷载作用下桩侧土的弱化效应及桩身侧向位移发展规律,提出了基于应变楔模型的砂土地基水平循环受荷桩简化分析方法。首先,利用砂土刚度衰减经验公式计算桩侧土刚度的弱化程度,确定循环再加载过程中桩侧土体应力-应变关系;其次,将其引入到应变楔模型中计算桩基侧向位移响应,考虑循环荷载作用次数和荷载大小的影响;最后,通过试验对比分析,验证所提方法能有效计算桩基础在水平循环荷载作用期间侧向位移的发展趋势。结果表明:桩身侧向位移随荷载作用次数增大而增加,其发展模式与荷载幅值大小相关;循环荷载作用下桩基水平承载能力存在较大程度的弱化。In order to reflect the influence of cyclic lateral load on the weakening effect of pile surrounding soil and the development law of pile lateral displacement, a simplified analysis method for the bearing behavior of cyclic laterally loaded pile was proposed based on strain wedge model.The empirical formula of the stiffness attenuation of sand soil was firstly utilized to calculate the weakening degree of the stiffness of pile surrounding soil, which was further applied to determine the stress-strain relationship of soil during cyclic reloads.Then, this stress-strain relationship was introduced into the strain wedge model to calculate the lateral response of pile considering the effect of cycles number and loading amplitude.Finally, the proposed method was proved to be able to effectively calculate the development law of pile lateral displacement during the action of cyclic loads through the comparative analysis with the test cases.The results showed that, the pile lateral displacement increased with the number of cycles increased, and its development mode was related to the loading magnitude.The lateral bearing capacity of pile foundation would be weakened in a large degree by cyclic loads.

关 键 词：水平循环受荷桩 应变楔模型 刚度衰减 简化分析 侧向位移 

分 类 号：TU473[建筑科学—结构工程]